V medicine is clearly one of their most powerful recruitment tools, and it's apparently working on Chad. His V surgery to prevent a brain aneurysm that human technology could not even see has led him not only to publicly embrace and endorse the Visitors, but now serve as their secret agent, seeking information from Father Jack. But given the possibility, even likelihood, that Chad will bump into some monstrous V plan on the ship, I wouldn't be shocked if he were to turn into a double agent - working for humans as he pretended to work for Anna - before too long. More shades of gray.
Ryan and Valerie barely escape a V Terminator-like "soldier" in one of the best action sequences of the series. But Valerie wants to go it alone - she can't (yet) forgive Ryan for not letting her know that he was a Visitor.
And it looks as if Lisa is not abandoning the human sensitivity that was picked up on her scan last week. In a significant scene, she tells Tyler not to take up permanent residence on the ship - this against Anna's express desires. Her feelings for Tyler are counting more than loyalty to her mother, a human thing to do in any situation, even when your mother is not a lizard from space invading Earth.
The spectrum of characters, pro and con the Visitors, has the excellent effect of making most of the characters unpredictable, which keeps us on edge and continues to be one of the most appealing aspects of this series.
See also V Returns to TV ... V 1.2: The Effects and The Characters ... V 1.3: Multiple Twists and Lizard Visions ... V 1.4: Good Medicine for Television ... V's Back in 1.5 ... V 1.6: Floating Witches ... V 1.7: Ryan's Story ... V 1.8: Is Lisa Becoming 5th Column?